Method and apparatus for blending finely granulated materials



June 17, 1969 KARL-HEINZ KAYATZ 3,449,842

METHOD AND APPARATUS FOR BLENDING FINELY GRANULATED MATERIALS Filed Aug. 2, 1967 Sheet of 2' June 17, 1969 KARL-HEINZ KAYATZ 3,449,842

METHOD AND APPARATUS FOR BLENDING FINELY GRANULATED MATERIALS Filed Aug. 2, 1967 United States Patent "ce 3,449,842 METHOD AND APPARATUS FOR BLENDING FINELY GRANULATED MATERIALS Karl-Heinz Kayatz, Hamburg-Nieustedten, Germany, assignor to Fuller Company Filed Aug. 2, 1967, Ser. No. 658,003 Claims priority, application Germany, Aug. 5, 1966,

Int. Cl. F26b 25/10; E6411 7/34; B65g 53/18 US. Cl. 34237 13 Claims ABSTRACT OF THE DISCLOSURE An aeration unit for blending silos having a sheet steel framework covered at its upper edges by an air-permeable plate and open at the bottom with cut out portions at the lower edges of the unit so as to receive the air supply lines having vertical gas nozzles attached and at the same time be substantially flush with the silo floor so as to be capable of being held firmly in place by a solidifying filler material, which also acts as a seal, deposited on the silo floor.

The method of installing such units and completing the construction of the aerated silo floor being briefly that of (1) laying the air supply lines, (2) laying the solidifying filler material to a depth just covering the supply lines but not of sufficient depth to cover the gas nozzles, and (3) placing the units in position over the supply lines and gas nozzles and embedding each into the filler.

BACKGROUND OF THE INVENTION air distribution boxes, consist of a cast iron or pressed steel frame having a fully enclosed bottom-wall and covered on top by an air-permeable plate of a suitable material. This plate is fitted into the frame so as to fit airtight. The air distribution boxes are singly connected to compressed air supply lines by a pipe coupling located at the frame. After assembly of the compressed air supply lines and fastening of the air distribution boxes, the .interspaces between the boxes and above the compressed air supply lines are usually filled.

v The aeration floor area available when laying out the entire silo floor with these known aeration boxes'is never greater than This failure 'to be able to'utilize the entire silo floor space is due on the one hand, to the relatively great distance between the boxes needed for the installation of the compressed air supply lines, and, on the other hand, to the relatively large area taken up by the joints for fastening the aeration plates.

The disadvantages of such known systems are readily apparent. These disadvantages are, among others: (1) the .total amount of material needed for fabricating the aerationunit frames is expensive, (2) the fabrication of the aeration units is complex and costly, (3) the available silo floor space is not fully utilized, and (4) the installa tion of the aerator system' including the connection of the aeration units with the air supply lines is complicated, time consuming, and costly.

3,449,842 Patented June 17, 1969 SUMMARY It is therefore a principal object of the present invention to provide an improved aeration unit construction which is of simpler construction and easier and less costly to install than any known systems heretofore.

Another object of the present invention is to provide an improved method of installing a compressed gas, usually air, aerating system on the floor of a blending silo.

Another object of the present invention is to provide an improved aeration unit which by its construction makes possible the utilization of a greater amount of aeratable floor area than known aeration units per any given blending silo.

Another object of the present invention is to provide an aeration unit which is open at the bottom and adapted to receive and overlie the compressed gas/ air supply lines in such a manner as to preclude the necessity of having to physically connect the gas supply lines to each and every aeration unit and to further provide a completely sealed aeration unit by the method of embedding the same in a preferably solidifying filler material such as concrete.

The foregoing and other objects and advantages are achieved by providing an aeration unit which is preferably entirely open at its underside. Thereby, an aeration floor made with aeration units according to the invention is so constructed that the compressed gas supply lines, having gas outlet openings assigned to the various aeration units, are not directly connected to the units, but are merely sealed within the units by means of a filler material, preferably one which will solidify, such as concrete. For example, fabrication may be effected in such a manner that the compressed gas supply lines are first laid out on the floor, that the various units are then placed over the lines located by the openings of the underside of the units and that the joints between the various units are subsequently filled in, whereby a seal between the lines and the unit walls is produced at the same time. Two side surfaces of the aerating units facing each other may have, according to the invention, cut-outs at their lower edge, matching the outside dimensions of a compressed gas supply line.

One especially preferred embodiment of a silo floor is characterized in that the compressed gas supply lines are located entirely within a solidifying filler substance and one gas nozzle extending upwardly from a supply line assigned to each of the various boxes protrudes beyond the filler surface, and that the lower edges of the respective side surfaces of the units is embedded into the-filler material. The preferred method of installing an aeration system havingthe aeration units of the present invention includes the steps of: first, the compressed gas supply lines with their respective gas nozzles assigned to the various aeration units are laid out on the silo floor; second, the floor is filled with a solidifying filler material, such as a concrete paste, to cover the compressed air supply lines, but not the gas nozzle openings; and finally, the units are pushed into the concrete paste over the gas nozzles. Thereby, the cut-outs in the aeration unit side surfaces straddle the compressed gas supply lines, whereby the units obtain at the same time a secure position substantiallyrfiush with one another at their top surface. I

A particularly preferred construction of each aeration unit consists of a box shaped unit having simple sidewalls whose upper edges have provisions for holding a gas permeable medium such as a form-closingly hardened, gaspermeable plate molded into the unit itself. The sidesurfaces may simply be stamped out of sheet metal, whereby the holding provisions have the shape of a bead oriented inward. The bead may be either continuous or non-continuous around the entire periphery of the side surfaces of each unit. It is preferred that the bead be noncontinuous, but yet extend transversely across a substantial portion of each unit. In addition, it may be expedient to provide reinforcements for the permeable plate which, for example, may be welded to opposing side walls.

It may be advantageous to provide in that part of the side walls which is to be sunk into the filler substance, additional cut-outs through which the concrete penetrates. This makes for reliable locking of the units in the filler substance.

The advantages of the aeration units or boxe according to the present invention and of the method for making the completed aerated silo floor by using such aeration units are, among others: the individual aeration units are considerably cheaper because they require less material due to the lack of a bottom, the units are easier to fabricate for the same reason and the installation of the units at the site i considerably simple and provides a substantial increase in free aeration area.

Other features and advantages will hereinafter appear.

As this invention may be embodied in several forms without departing from the spirit of essential characteristics thereof, the present embodiment is therefore illustrative and not restrictive, since the scope of the invention is defined by the appended claims rather than by the description preceding them, and all changes that fall within the metes and bounds of the claims, are therefore intended to be embraced by the claims.

Further objects and advantages will become more apparent from a consideration of the following detailed description taken in conjunction with the sole drawing which schematically shows a vertical section through a portion of a silo fioor and a section through a built-in aeration unit or box.

DESCRIPTION OF PREFERRED EMBODIMENTS Referring now to the drawing, the aeration units according to the preferred construction of the present invention are preferably of box shape having rectangular sheet steel frame 1 and no bottom wall. Below the upper edge of the box extends a bead 2, pushed in toward the inside and serving to the hold the gas permeable aeration medium in this case shown to be a permeable plate 3 having a ceramic base. However, such permeable medium can also be of metal or plastic base, or of a fabric of natural or synthetic fibers, or their equivalents. In addition, a reinforcing bracket 4, may be welded across the narrow side of the box. Provided in the long side walls of the rectangular box are cut-outs 5 for the gas (preferably air) supply line 6. The cut-outs may have the height and width dimensions to match the outside diameter of the air supply line 6. The material for the permeable plate 3, preferably a setting mixture, is introduced and mechanically shaken into the box in paste form. The preferred thickness of the plate may amount to 50 mm., for example. The plate is held by the inwardly orientated bead 2, running all around frame 1, and by reinforcing bracket 4, which is preferably embedded in the center of the plate. After the plate material introduced has set, the aeration box is ready for installation.

A preferred method of installing the aeration box in the silo is as follows:

First, the compressed gas supply lines are laid in the usual manner on the silo 7. Then the silo floor is filled with as pasty a solidifying filler, preferably concrete, as possible, to a height high enough for the concrete layer to cover the supply lines 6 by 2-4 cm., for example. The air outlet nozzles 9 protrude out of the liquid concrete layer.

The aeration boxes are now pushed into the concrete paste 8 from above in such a manner that their cut-outs 5 straddle the gas supply lines 6. Located in the middle of each box is then a gas outlet nozzle 9 with openings preferably disposed at the periphery. Therefore, the hitherto usual connection of each box to the gas supply line by means of pipe or hose connections and appropriate screw connection is now not required.

When pushing the boxes into the concrete paste, all interspaces between the various boxes, between the cutouts 5 and the gas supply lines 6 fill up with concrete and, after setting, cause the entire system to be sealed. The clamping forces between the boxes can be increased additionally by providing in the side walls of the sheet metal frame circular cut-outs 10, for example, through which the pasty concrete can penetrate, effecting the clamping after the concrete has set.

After the concrete bed 8 has hardened, the aerating floor is operative. The small interspaces still present between the various aeration boxes above the concrete bed impair the air-tightness of the system in no way. They may be filled with any suitable material, such as sand or the like, if desired. Otherwise, at least certain bulk materials introduced into the silo for blending will themselves seal these spaces.

An additional preferred method step includes that of placing a protective cap over each air nozzle before pouring the concrete. This prevents the concrete from plugging the nozzle. It has been found particularly advantageous to use a cap which will extend upwardly a greater height than that of the aeration boxes, thus preventing the possibility of installing the aeration box before first removing the air nozzle cap.

I claim:

1. A gas permeable aeration unit adapted for use in a blending silo aeration system and the like as one of a plurality of similar units constituting the porous media plenum chamber overlying a system of gas supply lines situated on the floor of the silo, comprising an enclosed side wall portion and a top wall portion, said unit being at least partially open at the bottom, said top wall portion including a gas permeable medium means so as to allow gas under pressure to pass therethrough, securing means for holding said top wall portion in fixed relation relative to said side wall portions, said securing means including a head on one of said wall portions and a corresponding interfitting depression in the other said wall portions, and said side wall portion including an opening located at the bottom thereof and spaced from said permeable medium means and adapted to receive at least one of said gas supply lines.

-2. A gas permeable aeration unit adapted for use in a blending silo aeration system and the like as one of a plurality of similar units constituting the porous media plenum chamber overlying a system of gas supply lines situated on the floor of the silo, comprising an enclosed side wall portion and a top wall portion, said unit being at least partially open at the bottom, said unit being in the form of a rectangular box having opposite side walls, said top wall portion including a gas permeable medium means so as to allow gas under pressure to pass therethrough, securing means for holding said top wall portion in fixed relation relative to said side wall portion, and said securing means including a bead on one of said wall portions and a corresponding interfitting depression in the other side wall portions.

3. A gas permeable aeration unit adapted for use in a blending silo aeration system and the like as one of a plurality of similar units constituting the porous media plenum chamber overlying a system of gas supply lines situated on the floor of the silo, comprising, an enclosed side wall portion and a top wall portion, said unit being at least partially open at the bottom, said unit being in the form of a rectangular box having opposite side walls, said top wall portion including a gas permeable medium means so as to allow gas under pressure to pass therethrough and the top surface thereof being substantially flush with the top surface of said side walls, securing means for holding said top wall portion in fixed relation relative to said side wall portion, said securing means including a head on one of said wall portions and a corresponding interfitting depression in the other said wall por tions, and at least one pair of said oppositely disposed side walls having aligned respective first cut-out portions located at the bottom thereof and spaced from said permeable medium means and adapted to receive atleast one of said gas supply lines.

4. A gas permeable aeration unit adapted for use in a blending silo aeration system and the like as one of a plurality of similar units constituting the porous media plenum chamber overlying a system of gas supply lines situated on the floor of the silo, comprising, an enclosed side wall portion and a top wall portion, said unit being fully open at the bottom, said unit being in the form of a rectangular box having opposite side walls, said top wall portion including a gas permeable medium means so as to allow gas under pressure to pass theret-hrough and the top surface thereof being substantially flush with the top surface of said side walls, said permeable medium means including a hardened plate having a ceramic base, reinforcing means in said top wall portion for increasing its strength, said reinforcing means including .at least one metal bar fixed to at least one pair of said opposite side walls, securing means for holding said top wall portion in fixed relation relative to said side wall portion, said securing means including a bead on one of said wall portions and a corresponding interfitting depression in the other said wall portions, at least one pair of said oppositely disposed sidewalls having aligned respective first cut-out portions located at the bottom thereof and spaced from said permeable medium means and adapted to receive at least one of said gas supply lines, and at least one said side walls having at least one additional opening adapted for aiding in the securement of the casing to the silo floor.

r 5. In a blending apparatus for uniformly mixing solid materials comprising a silo and a network of gas supply lines placed at the bottom of the silo having a plurality of gas outlet means for introducing compressed gas into a plurality of individual gas permeable units and wherein each gas permeable unit includes a gas permeable upper wall portion for permitting aeration of the solid materials disposed above, the improvement comprising,

(a) at least one of said gas permeable units being at least partially open at the bottom, said one unit including a side wall portion having a cut-out portion open at the lower edge thereof and said cut-out portion being in overlying relation with at least one of said gas supply lines, and

(b) a sealing filler material being situated on the floor of the silo and at least partially embedding said plurality of gas supply lines, the upper surface of said sealing filler material being in spaced relation with said permeable upper wall portion so as to form a plenum chamber.

6. In a blending apparatus for uniformly mixing solid materials comprising a silo and a network of gas supply lines placed at the bottom of the silo having a plurality of gas outlet means for introducing compressed gas into a plurality of individual gas permeable units and wherein each gas permeable unit includes a gas permeable upper wall portion for permitting aeration of the solid materials disposed above, the improvement comprising,

(a) at least one of said gas permeable units being at least partially open at the bottom, said one unit including a side wall portion having a cut-out portion open at the lower edge thereof and said cut-out portion being in overlying relation with at least one of said gas supply lines,

(b) a sealing filler material being situated on the floor of the silo and at least partially embedding said plurality of gas supply lines, the upper surface of said sealing filler material being in spaced relation with said permeable upper wall portion so as to form a plenum chamber, said gas outlet means including at least one gas nozzle enclosed by each said unit, and

(c) holding means for holding said permeable upper wall portion in fixed relation with said side wall portion, said holding means including bead means on one of said portions and corresponding interfitting groove means on the other of said portions.

7. In a blending apparatus for uniformly mixing solid materials comprising a silo and a network of gas supply lines placed at the bottom of the silo having a plurality of gas outlet means for introducing compressed gas into a plurality of individual gas permeable units and wherein each gas permeable unit includes a gas permeable upper wall portion for permitting aeration of the solid materials disposed above, the improvement comprising,

(a) at least one of said gas permeable units being fully open at the bottom, said one unit including a side wall portion having a cut-out portion open at the lower edge thereof and said cut-out portion being in overlying relation with at least one of said gas supply lines,

(b) a sealing filler material being situated on the floor of the silo and at least partially embedding said plurality of gas supply lines, the upper surface of said sealing filler material being in spaced relation with said permeable upper wall portion so as to form a plenum chamber.

8. In a blending apparatus for uniformly mixing solid nuaterials comprising a silo and a network of gas supply a plurality of individual gas permeable units and wherein each gas permeable unit includes a gas permeable upper wall portion for permitting aeration of the solid materials disposed above, the improvement comprising,

(a) at least one of said gas permeable units being at least partially open at the bottom, said one unit including a side wall portion having a cut-out portion open at the lower edge thereof and said cut-out portion being in overlying relation with at least one of said gas supply lines,

(b) a sealing filler material being situated on the floor of the silo and at least partially embedding said plurality of gas supply lines, the upper surface of said sealing filler material being in spaced relation with said permeable upper wall portion so as to form a plenum chamber,

(c) said gas outlet means including at least one gas nozzle enclosed by each said unit,

(d) said side wall portion of said one unit further including securing means for securing the unit in said sealing filler material, said securing means including at least one additional cut-out portion in the side wall portion of said one unit, said additional cut-out portion being fully disposed in said sealing filler material,

(e) holding means for holding said permeable upper wall portion in fixed relation with said side wall portion, said holding means including bead means on one of said portions and corresponding interfitting groove means on the other of said portions,

(if) said permeable upper wall portion further including reinforcing means embedded therein, said reinforcing means including at least one substantially rigid metal bar fixed to said side wall portion of said one unit,

(g) each of said gas permeable units being in closely spaced relation to one another and said sealing filler material extending between said spaced units, and

(h) means for sealing the spaces between the individual units at least at the upper wall portions.

9. A method for installing an aerated floor for blending silos and the like which comprises, laying a network of compressed ga supply lines at the floor of the silo, filling the silo floor area with a solidfying filler material to a height so as to sealingly enclose said supply lines, placing at least one permeable aeration unit over said supply lines and pushing said aeration unit downwardly into said filler material until said unit is sealingly embedded in said filler material together with said gas supply lines.

10. A method for installing an aerated floor for blending silos and the like which comprises, laying a network of compressed gas supply lines, each line having at least one upwardly projecting gas outlet means, at the floor of the silo, filling the silo floor area with a solidfying filler material to a height at least equal to that of said gas supply lines so as to sealingly enclose said supply lines keeping said filler material free of said gas outlet means so as to permit unobstructed discharge of gas therefrom, placing at least one gas permeable aeration unit over said supply lines so as to encompass 'at least one of said gas outle't means, and pushing said aeration unit downwardly into said filler material until said unit is sealingly embedded in said filler material together with said gas supply lines.

11. A method for installing an aerated floor for blending silos and the like which comprises, laying a network of compressed gas supply lines, each line having at least one upwardly projecting gas outlet means, at the floor of the silo, filling the silo floor area with a solidifying filler material to a height at least equal to that of said gas supply lines so as to sealingly enclose said supply lines, keeping said filler material free of said gas outlet means so as to permit unobstructed discharge of gas therefrom, placing at least one gas permeable aeration unit over said supply lines so as to encompass at least one of said gas outlet means, and pushing said aeration unit downwardly into said filler material until said unit is sealingly embedded in said filler material together with said gas supply lines at a depth contacting the floor of said blending silo.

12. A method for installing an aerated floor for blending silos and the like which comprises, laying a network of compressed gas supply lines, each line having at least one upwardly projecting gas outlet means, at the floor of the silo, placing a protective cap means over said gas outlet means, filling the silo floor area with a solidifying filler material to a height at least equal to that of said gas supply lines so as to sealingly enclose said supply line, keeping said filler material free of said gas outlet means so as to permit unobstructed discharge of gas therefrom, removing said protective cap means,

placing at least one gas permeable aeration unit over said supply lines so as to encompass at least one of said gas outlet means, and pushing said aeration unit downwardly into said filler material until said unit is sealing ly embedded in said filler material together with said gas supply lines.

13. A method for installing an aerated floor for blend ing silos and the like which comprises, laying a network of compressed gas supply lines, each line having at least one upwardly projecting gas outlet means, at the floor of the silo, placing a protective cap means over said gas outlet means, filling the silo floor area with a solidifying filler material to a height at least equal to that of said gas supply lines so as to sealingly enclose said supply lines, keeping said filler material free of said gas outlet means so as to permit unobstructed discharge of gas therefrom, removing said protective cap means, placing at least one gas permeable aeration unit over said supply lines so as to encompass at least one of said gas outlet means, and pushing said aeration unit downwardly into said filler material until said unit is sealingly embedded in said filler material together with said gas supply lines at a depth contacting the floor of said blending silo.

References Cited UNITED STATES PATENTS 10,370 1/1854 Stewart 34-237 27,237 2/1860 Smith 34237 80,110 7/1868 Arnold 34-237 233,301 10/1880 Toepfer 34237 1,538,743 5/1925 Prickett 5274l 2,316,814 4/ 1943 Schemm. 2,524,331 10/1950 Rysdon 9855 2,901,960 9/1959 Barre et al 98-55 3,073,651 1/1963 Leimegger 30229 3,172,740 3/1965 Elstner 9852 X 3,279,094 10/1966 Blanton 34-233 FREDERICK L. MATTESON, JR., Primary Examiner.

R. A. DUA, Assistant Examiner.

US. Cl. X.R. 9855 

